Field of the Invention
The present invention relates to a charging member, and a process cartridge and an electrophotographic image forming apparatus including the charging member (hereinafter, referred as “electrophotographic apparatus”).
Description of the Related Art
One of methods of charging the surfaces of electrophotographic photosensitive members (hereinafter referred as “photosensitive members”) is a contact charging method. In the contact charging method, voltage is applied to a charging member disposed on the photosensitive member to be in contact therewith and very small discharge is generated near the contact portion between the charging member and the photosensitive member to charge the surface of the photosensitive member.
A typical configuration of the charging member used in the contact charging method includes an electro-conductive elastic layer to obtain a desired electric resistance. Japanese Patent Application Laid-Open No. H04-77766 proposes disposition of a resin layer containing a hydroxystyrene resin on an electro-conductive elastic layer to reduce a fluctuation in electric resistance of the electro-conductive elastic layer according to the environment for use.